1. Field of the Invention
This invention relates to a structure for electrical connection of an electric part, such as an IC, a wiring board, and the like.
2. Brief Description of the Related Art
As shown in FIG. 1, there is known a contact probe 1 constituted of a wire material entangled and formed into a rod-like configuration. In a conventional socket, this contact probe 1 is implanted in a through-hole 3 formed in an insulating substrate 2 and a contactor 5 of an IC 4 is caused to directly overlie and contact one end of the contact probe 1 in order to establish an electrical connection.
However, in the above-mentioned structure for electrical connection, since the IC contactor 5 is vertically descended merely to vertically compress the contact probe 1 along the axis of the through-hole, a sufficient wiping effect cannot be obtained with respect to the contact interface and as a result, a stable electrical connection is difficult to obtain.
Recently, as it has become increasingly necessary to arrange the IC contactors at very narrow pitches, the contact probes are also required to be made thinner and thinner and arranged at narrower pitches. However, in the above-mentioned structure for electrical connection in which the IC contactor is caused to directly overlie and contact the contact probe, the area of the contact probe is very limited and therefore, it is difficult to employ a zigzag arrangement of the contact probes in order to fulfill the increasing requirement for the narrower pitch arrangement.
On the other hand, the contact probe of the type in which the contact probe is compressed in the axial direction of the through-hole is convenient in that a stable physical contact position can be obtained because the contact probe is not one-sided sideways as in the case of a horizontal U-shaped contactor having a long stroke of a spring, and in that the signal line length is reduced to obtain a favorable characteristic with respect to a high frequency signal.
The present invention has been accomplished in view of the above-mentioned drawbacks inherent in the conventional devices.